Instrument panel delete/alternator light

#1

Deleting the panel. I have the alternator wires (blue & green) that run to and from the cluster. Inside the cluster they run through a bulb and resistor (if the bulb burns out). Can I just connect the two wires without a light or resistor or does one or both of those things have to stay inline?

Also any pitfalls I need to be aware of? Not using stock senders btw.

#2

No…if you just connect the wires, the motor will not kill with the kill switch. It back feeds from the alternator. You must install a blocking diode between the two wires. Try both orientations for proper installation.

#3

Good point. Couldn’t I just run it through a relay powered by the small terminal output of the load side of the kill switch?

#4

That line is actually the exciter for the alt. Relay may work, but diodes are extremely cheap and dead reliable. I put them between two of the pins on the blue (I think) connector to the panel.

#5

what amp/v rating should i use on the diode? radio shack has a ton of options.

#6

Probably under 1A…been too long since I bought. I do remember paying about $2 for two.

#7

Revival. I ended up using a 4.7 Ohm 5W 5% Axial Lead Wire Wound Cement Resistor and it is hotter than the sun. Any other alternatives that accomplish this without burning up?

#8

5W isn’t much of a resister. Get something like a 25W or bigger resister then epoxy it to a piece of metal.

Note, however, that I don’t know anything about the alternator’s exciter. I’m only addressing the issue of the resister being too hot.

#9

Well this one worked so I’ll try to find the same ohm rating. Is that correct thinking?

#10

Yes, roughly the same ohms, doesn’t have to be exact. Just get it as a big beefy high watt resister. Then epoxy it to a piece of metal. That last part is the important part because the metal it’s fastened to will be the heatsink.

Now that I think about it, going higher in ohms would be better than lower. Like maybe get several big resisters of various higher values. The higher the ohms (resistance), the less current will try to flow thru the thing. The lower the current the less heat has to be dumped elsewhere.